A team of University of Iowa scientists has now discovered that tomatidine, a compound from green tomatoes, is even more potent for building muscle and protecting against muscle atrophy.

"Muscle atrophy causes many problems for people, their families, and the health care system in general. Exercise certainly helps, but it is not enough and not very possible for many people who are ill or injured," said Christopher Adams, an associate professor of internal medicine and molecular physiology and biophysics.

Muscle atrophy, or wasting, is caused by aging and a variety of illnesses and injuries, including cancer, heart failure, and orthopaedic injuries, to name a few.

It makes people weak and fatigued, impairs physical activity and quality of life, and predisposes people to falls and fractures.

Adams and his team zeroed in on tomatidine using a systems biology tool called the Connectivity Map.

Adams discovered that tomatidine generates changes in gene expression that are essentially opposite to the changes that occur in muscle cells when people are affected by muscle atrophy.

After identifying tomatidine, Adams and his team tested its effects on skeletal muscle.They first discovered that tomatidine stimulates growth of cultured muscle cells from humans.

Their next step was to add tomatidine to the diet of mice.

They found that healthy mice supplemented with tomatidine grew bigger muscles, became stronger and could exercise longer.

And, most importantly, they found that tomatidine prevented and treated muscle atrophy.

"Interestingly, although mice fed tomatidine had larger muscles, their overall body weight did not change due to a corresponding loss of fat, suggesting that the compound may also have potential for treating obesity," Adams noted.

"Green tomatoes are safe to eat in moderation. But we still do not know how many green tomatoes a person would need to eat to get a dose of tomatidine similar to what we gave the mice. We are working hard to answer this," Adam explained.

The study was published online in the Journal of Biological Chemistry.